Source Code for In-person schooling and associated COVID-19 risk in the United States over Spring Semester 2021

Kirsten E. Wiens, Claire P. Smith, Elena Badillo-Goicoechea, Kyra H. Grantz, M. Kate Grabowski, Andrew S. Azman, Elizabeth A. Stuart, Justin Lessler


Code is provided to reproduce the primary in-person schooling (1-Main-Schooling-Analysis.Rmd) and occupation/work outside home (2-Educators-Analysis.Rmd) analyses using a synthetic dataset. Hence, results produced when knitting these documents will not match those presented in the accompanying paper.

Data to reproduce paper figures/tables are freely available from the CMU Delphi Research Group to researchers at universities and non-profits as detailed at Getting Data Access - Delphi Epidata API (cmu-delphi.github.io).

Please reach out to justin[at]jhu.edu if you have any questions.

Table S1

Sociodemographic characteristics of participants with ≥1 school-aged child in the household, comparing those reporting no in-person schooling to those reporting any part-time and full-time in-person schooling. Observed and survey-weighted percentages reported.

Table S2

Monthly COVID-19-related outcomes in different subsets of US CTIS respondents, including total number, observed percent, and percent weighted to account for survey design.

Figure 1

Changes over time in in-person schooling by county. Distribution of survey responses from Jan. 12 to Mar. 31 (left column), Apr. 1 to Jun. 12 (center column) and change over time (right column). Results are shown for (A) number of survey respondents reporting ≧1 school-aged child in the household, (B) percent reporting in-person schooling, (C) percent of respondents with in-person schooling reporting full-time in-person instruction, and (D) average number of school-based mitigation measures. “Relative Amount” in the right column indicates values in Apr. 1 to Jun. 12 (center column) divided by values in Jan. 12 to Mar. 31 (left column). Grey indicates county/periods where fewer than 10 respondents reported in-person schooling.

Figure 2

Concurrent changes in in-person schooling, vaccination, and variant prevalence. Changes over time between Jan. 12 and Jun. 12 in (A) percent of respondents living with school-aged children reporting any in-person schooling, (B) average number of school-based mitigation measures, (C) smoothed percent of GISAID SARS-CoV-2 sequenced isolates that were Alpha or Delta, and (D) percent of respondents living with school-aged children reporting having received at least one COVID-19 vaccine dose. Upper panel line plots show national averages by week weighted using US CTIS survey weights (A-B), state population (C), and county population (D). Lower panel histograms show the number of county-months with the indicated percentages (A,C,D) or numbers (B). Note that the number of respondents decreased over time (Fig 1d), which may contribute to the increasing number of zero values in the histograms in June.

Movie S1

Changes in in-person schooling, vaccination, and variant prevalence. Top left: County-level smoothed weekly estimates of percent of individuals living with school-aged children participating in part-time or full-time in-person schooling. Top right: County-level smoothed weekly estimates of the percent of individuals living with school-aged children that had received any number of COVID-19 vaccine doses. Bottom left: State-level smoothed weekly estimates of the proportion of circulating SARS-CoV-2 strains that were the Alpha variant. Bottom right: State-level smoothed weekly estimates of the proportion of circulating SARS-CoV-2 strains that were the Delta variant. In-person schooling and vaccination estimated using United States COVID-19 Trends and Impact Survey data; counties with fewer than 20 respondents reporting in-person schooling excluded. Variant prevalence estimated using GISAID sequencing data. Dates represent the last day of each week.

Changes in in-person schooling, vaccination, and variant prevalence

Figure S1

Comparison of county-month vaccination rates between the survey and CDC data. (A) Proportion of survey respondents living with school-aged children that reported being vaccinated compared to all survey respondents. (B) Average monthly differences in proportion vaccinated between respondents living with school-aged children and all respondents by county. (C) Proportion of respondents living with school-aged children that reported being vaccinated compared to CDC-reported vaccination rates. (D) Average monthly differences in proportion vaccinated between survey respondents living with school-aged children and CDC reported vaccination rates by county. “Vaccinated” represents having received at least one COVID-19 vaccine dose. In (A,C) each point represents a county-month. Blue lines indicate fit smooth spline relationships, correlations are Pearson correlation coefficients, and slopes come from a simple linear regression. Limited to county-months with at least 5 survey respondents living with school-aged children (A-D) and at least 75% complete CDC data (C-D).

Figure 3

Risk associated with in-person schooling overall and by grade level. Odds ratios of COVID-19-related outcomes by full- and part-time in-person schooling compared to no in-person schooling, overall and stratified by grade, adjusted for individual- and county-level covariates across the study period from Jan. 12 to Jun. 12. Note: grade-stratified analyses include only those respondents who reported living with school-aged children in a single grade category, while the overall analyses include all respondents living with school-aged children; thus, the overall estimates do not always fall in-between the grade-specific estimates.

Figure S2

Risk associated with in-person schooling overall and by grade level. Odds ratios of COVID-19-related outcomes by full- and part-time in-person schooling compared to no in-person schooling, overall and stratified by grade, adjusted for individual- and county-level covariates. Results are shown stratified by time periods Jan. 12 to Feb. 28 (Jan-Feb), Mar. 1 to Apr. 30 (Mar-Apr), and May 1 to Jun. 12 (May-Jun). Note: grade-stratified analyses include only those respondents who reported living with school-aged children in a single grade category, while the overall analyses include all respondents living with school-aged children; thus, the overall estimates do not always fall in-between the grade-specific estimates.

Table S3

Relative odds of COVID-19-related outcomes by full- and part-time in-person schooling compared to no in-person schooling, either overall among respondents with school-aged children or stratified by grades among households with children in only a single grade.

Grade Loss of taste/smell COVID like illness Test+
adj. OR 95% CI adj OR 95% CI adj OR 95% CI
January to June
Full-time: K or under 3.30 2.90–3.82 3.80 3.12–4.79 3.35 2.91–3.92
Full-time: 1 to 5 2.89 2.62–3.21 3.18 2.74–3.77 4.04 3.51–4.72
Full-time: 6 to 8 3.10 2.70–3.63 2.89 2.43–3.56 3.43 2.90–4.15
Full-time: 9 to 12 3.51 3.11–4.01 3.49 2.94–4.27 4.39 3.74–5.25
Full-time: overall 3.43 3.28–3.59 3.99 3.72–4.30 3.84 3.64–4.06
Part-time: K or under 3.01 2.62–3.53 2.76 2.34–3.35 2.59 2.26–3.03
Part-time: 1 to 5 3.19 2.81–3.67 3.47 2.89–4.31 2.99 2.62–3.46
Part-time: 6 to 8 2.92 2.51–3.49 2.51 2.09–3.16 2.93 2.47–3.57
Part-time: 9 to 12 3.05 2.75–3.43 2.74 2.39–3.20 2.95 2.64–3.34
Part-time: overall 3.65 3.48–3.83 3.87 3.62–4.14 3.24 3.08–3.41
January to February
Full-time: K or under 3.32 2.81–4.03 4.31 3.23–6.19 3.53 2.97–4.33
Full-time: 1 to 5 2.95 2.60–3.40 2.90 2.37–3.70 3.77 3.22–4.50
Full-time: 6 to 8 3.13 2.61–3.88 3.19 2.45–4.49 3.30 2.72–4.15
Full-time: 9 to 12 3.37 2.86–4.06 3.51 2.79–4.66 4.15 3.45–5.13
Full-time: overall 3.39 3.20–3.60 4.02 3.65–4.47 3.69 3.46–3.95
Part-time: K or under 2.61 2.22–3.19 2.54 2.03–3.41 2.73 2.31–3.35
Part-time: 1 to 5 3.03 2.60–3.60 3.04 2.44–4.00 2.92 2.51–3.49
Part-time: 6 to 8 3.27 2.65–4.22 2.58 2.04–3.53 2.63 2.18–3.31
Part-time: 9 to 12 2.99 2.59–3.52 2.62 2.19–3.28 3.29 2.84–3.91
Part-time: overall 3.24 3.06–3.45 3.25 2.99–3.54 3.06 2.89–3.26
March to April
Full-time: K or under 3.27 2.66–4.19 3.47 2.63–4.96 3.14 2.49–4.21
Full-time: 1 to 5 2.71 2.32–3.26 3.08 2.48–4.03 4.46 3.35–6.34
Full-time: 6 to 8 3.22 2.56–4.29 2.57 2.04–3.46 3.31 2.49–4.80
Full-time: 9 to 12 3.72 3.03–4.75 3.57 2.69–5.15 4.92 3.64–7.14
Full-time: overall 3.54 3.28–3.85 4.13 3.69–4.66 4.10 3.70–4.57
Part-time: K or under 2.95 2.39–3.84 2.91 2.26–4.04 2.43 1.95–3.25
Part-time: 1 to 5 3.17 2.58–4.06 2.86 2.26–3.86 2.96 2.37–3.93
Part-time: 6 to 8 2.63 2.12–3.46 2.15 1.74–2.87 2.78 2.11–4.05
Part-time: 9 to 12 2.94 2.50–3.56 2.50 2.06–3.20 2.42 2.06–2.95
Part-time: overall 3.79 3.50–4.12 3.99 3.61–4.44 3.27 3.00–3.59
May to June
Full-time: K or under 3.20 2.30–5.08 3.52 2.36–6.33 2.70 1.71–6.19
Full-time: 1 to 5 3.00 2.29–4.27 3.67 2.49–6.35 3.74 2.38–7.44
Full-time: 6 to 8 2.64 1.98–3.93 2.98 1.99–5.63 3.80 2.18–9.90
Full-time: 9 to 12 3.11 2.38–4.39 2.95 2.16–4.55 3.72 2.25–8.34
Full-time: overall 3.16 2.80–3.62 3.55 3.01–4.28 3.65 2.98–4.64
Part-time: K or under 5.22 3.15–10.79 2.96 2.05–5.15 2.70 1.58–8.62
Part-time: 1 to 5 3.98 2.58–7.49 8.28 4.10–23.68 4.69 2.50–13.51
Part-time: 6 to 8 2.48 1.74–4.43 2.98 1.84–7.08 6.47 2.71–33.17
Part-time: 9 to 12 3.34 2.51–4.88 3.44 2.44–5.52 3.69 2.17–9.11
Part-time: overall 4.29 3.69–5.08 4.83 4.00–5.98 4.43 3.48–5.91

Figure 4

Individual mitigation measures. (A) Percent of respondents with in-person schooling that reported each mitigation measure being used in January and June, weighted using US CTIS survey weights. (B) Odds ratio of COVID-19-related outcomes among respondents with children in in-person schooling who reported each mitigation measure compared to those with children in in-person schooling who did not report each measure, adjusted for individual- and county-level covariates across the study period from Jan. 12 to Jun. 12.

Figure S3

Individual mitigation measures over time. Odds ratio of COVID-19-related outcomes among respondents living with children in in-person schooling who reported each mitigation measure compared to those living with children in in-person schooling who did not report each measure, adjusted for individual- and county-level covariates. Results are stratified by time periods Jan.12 to Feb. 28 (Jan-Feb), Mar. 1 to Apr. 30 (Mar-Apr), and May 1 to Jun. 12 (May-Jun).

Table S4

Relative odds of COVID-19-related outcomes among respondents living with children in in-person schooling by individual mitigation measures within different time periods.

Mitigation measure Loss of taste/smell COVID like illness Test+
adj. OR 95% CI adj OR 95% CI adj OR 95% CI
January to June
student masking 2.39 2.25–2.55 2.43 2.25–2.63 2.38 2.21–2.58
teacher masking 2.08 1.98–2.19 1.87 1.77–1.98 2.15 2.03–2.29
same teacher 2.58 2.43–2.75 2.76 2.54–3.03 2.71 2.53–2.91
same students 2.48 2.34–2.63 2.52 2.33–2.74 2.60 2.43–2.80
outdoor instruction 2.83 2.60–3.10 3.35 2.95–3.86 2.60 2.38–2.87
restricted entry 2.36 2.24–2.49 2.30 2.15–2.48 2.42 2.27–2.58
reduced class size 2.67 2.52–2.85 2.57 2.38–2.80 2.60 2.44–2.78
closed cafe 2.63 2.47–2.80 2.78 2.55–3.05 2.54 2.39–2.72
closed playground 3.12 2.88–3.41 3.73 3.29–4.27 3.06 2.80–3.36
desk shields 2.87 2.69–3.09 3.46 3.13–3.86 3.08 2.85–3.35
extra space 2.39 2.27–2.53 2.25 2.11–2.42 2.60 2.44–2.80
no extracurricular 2.94 2.74–3.17 2.71 2.48–3.00 2.33 2.20–2.49
no supply sharing 2.63 2.48–2.81 2.46 2.28–2.67 2.69 2.51–2.90
daily symptom screen 2.44 2.32–2.58 2.26 2.13–2.41 2.35 2.23–2.49
part time 3.17 2.99–3.36 3.19 2.96–3.46 2.79 2.63–2.96
January to February
student masking 2.28 2.11–2.47 2.39 2.15–2.70 2.27 2.09–2.49
teacher masking 2.22 2.07–2.41 1.93 1.78–2.11 2.32 2.13–2.54
same teacher 2.70 2.48–2.96 2.67 2.36–3.08 2.69 2.47–2.96
same students 2.45 2.27–2.67 2.54 2.25–2.93 2.60 2.39–2.86
outdoor instruction 2.61 2.35–2.94 3.18 2.68–3.89 2.45 2.21–2.76
restricted entry 2.36 2.20–2.56 2.19 1.99–2.43 2.42 2.24–2.62
reduced class size 2.58 2.39–2.80 2.69 2.40–3.07 2.56 2.37–2.77
closed cafe 2.65 2.44–2.90 2.80 2.46–3.24 2.65 2.44–2.89
closed playground 2.92 2.63–3.26 3.34 2.86–4.00 3.01 2.71–3.37
desk shields 3.00 2.74–3.31 3.69 3.18–4.38 2.96 2.70–3.27
extra space 2.44 2.26–2.64 2.39 2.15–2.71 2.66 2.43–2.92
no extracurricular 2.68 2.46–2.94 2.74 2.41–3.17 2.25 2.10–2.42
no supply sharing 2.50 2.32–2.72 2.37 2.14–2.66 2.69 2.47–2.95
daily symptom screen 2.37 2.22–2.54 2.14 1.98–2.35 2.26 2.12–2.42
part time 2.96 2.76–3.20 2.75 2.50–3.05 2.75 2.57–2.96
March to April
student masking 2.48 2.25–2.77 2.40 2.16–2.71 2.48 2.18–2.88
teacher masking 1.98 1.85–2.15 1.81 1.69–1.97 2.05 1.88–2.27
same teacher 2.60 2.37–2.89 2.79 2.47–3.21 2.54 2.28–2.86
same students 2.52 2.30–2.79 2.56 2.29–2.91 2.69 2.40–3.04
outdoor instruction 2.64 2.34–3.02 3.06 2.58–3.73 2.68 2.32–3.19
restricted entry 2.23 2.07–2.43 2.27 2.06–2.53 2.36 2.14–2.63
reduced class size 2.73 2.48–3.04 2.53 2.27–2.85 2.70 2.41–3.07
closed cafe 2.72 2.46–3.03 2.71 2.39–3.12 2.41 2.18–2.69
closed playground 3.45 3.00–4.05 4.61 3.72–5.91 3.17 2.70–3.82
desk shields 2.85 2.56–3.22 3.40 2.94–4.02 3.14 2.75–3.64
extra space 2.33 2.15–2.54 2.22 2.03–2.46 2.51 2.26–2.82
no extracurricular 3.10 2.75–3.55 2.87 2.49–3.37 2.56 2.27–2.94
no supply sharing 2.88 2.59–3.23 2.47 2.22–2.80 2.63 2.34–3.00
daily symptom screen 2.35 2.18–2.56 2.21 2.03–2.44 2.43 2.21–2.70
part time 3.20 2.93–3.53 3.26 2.92–3.69 2.68 2.44–2.98
May to June
student masking 2.48 2.11–3.01 2.51 2.10–3.12 2.55 1.92–3.83
teacher masking 2.01 1.78–2.33 1.90 1.66–2.25 1.74 1.48–2.18
same teacher 2.29 2.00–2.70 2.84 2.31–3.67 3.73 2.61–6.09
same students 2.43 2.09–2.91 2.38 2.00–2.97 2.36 1.86–3.29
outdoor instruction 3.99 3.04–5.61 4.32 3.10–6.64 3.13 2.14–5.55
restricted entry 2.56 2.20–3.06 2.59 2.17–3.22 2.76 2.13–3.89
reduced class size 2.85 2.42–3.47 2.55 2.09–3.27 2.45 2.00–3.20
closed cafe 2.42 2.09–2.90 2.91 2.36–3.79 2.49 1.99–3.35
closed playground 3.01 2.41–3.97 3.17 2.40–4.57 2.95 2.15–4.64
desk shields 2.62 2.22–3.19 3.15 2.51–4.19 3.36 2.47–5.09
extra space 2.45 2.13–2.89 2.11 1.83–2.52 2.70 2.10–3.78
no extracurricular 3.59 2.84–4.77 2.45 1.99–3.20 2.52 1.95–3.57
no supply sharing 2.46 2.12–2.94 2.60 2.13–3.33 3.02 2.26–4.46
daily symptom screen 2.79 2.37–3.39 2.60 2.18–3.23 2.65 2.13–3.54
part time 3.53 2.98–4.29 3.82 3.08–4.95 3.88 2.91–5.58

Figure S4

Individual mitigation measures and alternative COVID-19-related outcomes. Odds ratio of alternative COVID-19-related outcomes among respondents living with children in in-person schooling who reported each mitigation measure compared to those living with children in in-person schooling who did not report each measure, adjusted for individual- and county-level covariates across the Spring Semester 2021. Alternative COVID-19-related outcomes include COVID-like illness in any household member (blue), a household member testing positive for SARS-CoV-2 (green), and the survey respondent testing positive when the test was indicated (purple) and when it was not indicated (orange). High uncertainty around non-indicated positive tests reflects a small sample size (533 total non-indicated positive tests).

Figure 5

Risk associated with in-person schooling over time by number of reported mitigation measures. Odds ratio of COVID-19-related outcomes by full- and part-time in-person schooling and number of school-based mitigation measures compared to no in-person schooling, adjusted for individual- and county-level covariates. “Overall” indicates adjusted odds ratios of full-time and part-time schooling with any number of mitigation measures compared to no in-person schooling. Odds ratios are shown across the entire study period from Jan. 12 to Jun. 12. (Jan-Jun), as well as within time periods from Jan.12 to Feb. 28 (Jan-Feb), Mar. 1 to Apr. 30 (Mar-Apr), and May 1 to Jun. 12 (May-Jun).

Table S5

Relative odds of COVID-19-related outcomes by full- and part-time in-person schooling and either number of mitigation measures or overall compared to no in-person schooling within different time periods.

Number of mitigation measures Loss of taste/smell COVID like illness Test+
adj. OR 95% CI adj OR 95% CI adj OR 95% CI
January to June
Full-time: 0 5.63 4.22–7.98 5.57 4.01–8.37 7.96 4.82–15.38
Full-time: 1-3 4.20 3.82–4.64 4.59 4.02–5.31 4.90 4.34–5.58
Full-time: 4-6 2.52 2.37–2.69 2.34 2.16–2.56 3.49 3.19–3.85
Full-time: 7-9 2.55 2.40–2.72 2.32 2.14–2.53 2.83 2.63–3.06
Full-time: 10+ 2.28 2.12–2.46 2.53 2.27–2.87 2.65 2.43–2.91
Full-time: Overall 3.30 3.16–3.46 3.75 3.50–4.04 3.75 3.55–3.97
Part-time: 0 5.93 3.69–11.29 7.46 4.05–17.91 5.16 3.08–10.90
Part-time: 1-3 3.44 3.05–3.92 3.51 2.99–4.22 3.04 2.68–3.50
Part-time: 4-6 2.95 2.62–3.37 2.20 1.93–2.57 3.15 2.78–3.62
Part-time: 7-9 2.40 2.21–2.63 1.93 1.76–2.13 2.39 2.20–2.62
Part-time: 10+ 2.10 1.93–2.31 1.84 1.68–2.03 2.20 2.03–2.40
Part-time: Overall 3.41 3.25–3.58 3.53 3.31–3.77 3.09 2.94–3.25
January to February
Full-time: 0 6.92 4.47–12.16 6.12 3.59–13.00 6.11 3.78–11.77
Full-time: 1-3 4.26 3.75–4.90 5.22 4.28–6.53 4.36 3.77–5.11
Full-time: 4-6 2.73 2.50–3.01 2.47 2.18–2.86 3.70 3.30–4.19
Full-time: 7-9 2.54 2.33–2.78 2.32 2.07–2.65 2.89 2.63–3.20
Full-time: 10+ 2.25 2.05–2.50 2.51 2.15–3.02 2.61 2.35–2.94
Full-time: Overall 3.29 3.10–3.49 3.75 3.41–4.15 3.61 3.39–3.86
Part-time: 0 5.31 2.94–13.26 5.64 2.62–22.40 3.66 2.08–9.91
Part-time: 1-3 3.70 3.12–4.50 3.46 2.77–4.53 3.14 2.68–3.77
Part-time: 4-6 3.05 2.63–3.60 2.31 1.95–2.86 3.42 2.92–4.11
Part-time: 7-9 2.44 2.20–2.75 2.11 1.85–2.49 2.60 2.33–2.93
Part-time: 10+ 1.90 1.75–2.10 1.84 1.63–2.12 2.11 1.92–2.34
Part-time: Overall 3.14 2.96–3.34 3.12 2.87–3.41 2.98 2.81–3.18
March to April
Full-time: 0 5.56 3.62–9.84 6.65 3.86–14.32 13.35 4.91–68.24
Full-time: 1-3 4.26 3.65–5.05 4.33 3.57–5.41 5.37 4.34–6.86
Full-time: 4-6 2.37 2.17–2.62 2.21 1.98–2.51 3.33 2.85–3.99
Full-time: 7-9 2.51 2.28–2.79 2.31 2.05–2.65 2.75 2.44–3.15
Full-time: 10+ 2.20 1.97–2.51 2.47 2.11–2.99 2.69 2.31–3.21
Full-time: Overall 3.35 3.10–3.63 3.81 3.42–4.29 3.99 3.60–4.45
Part-time: 0 5.86 3.03–16.79 7.18 3.06–32.35 8.18 3.48–34.67
Part-time: 1-3 3.19 2.65–3.98 3.41 2.68–4.60 2.81 2.30–3.60
Part-time: 4-6 2.76 2.29–3.49 1.97 1.68–2.41 2.91 2.38–3.73
Part-time: 7-9 2.27 2.01–2.61 1.72 1.53–1.99 2.10 1.84–2.45
Part-time: 10+ 2.30 1.96–2.80 1.91 1.66–2.27 2.26 1.96–2.69
Part-time: Overall 3.49 3.23–3.79 3.60 3.27–4.00 3.11 2.85–3.42
May to June
Full-time: 0 4.02 2.40–9.20 3.50 2.29–6.62 4.61 1.88–40.78
Full-time: 1-3 3.58 2.91–4.58 3.90 2.97–5.48 4.81 3.24–8.16
Full-time: 4-6 2.26 1.96–2.69 2.24 1.89–2.78 2.41 1.92–3.27
Full-time: 7-9 2.52 2.13–3.10 2.18 1.82–2.76 2.27 1.82–3.08
Full-time: 10+ 2.48 2.02–3.22 2.59 1.97–3.81 2.29 1.73–3.51
Full-time: Overall 3.06 2.71–3.50 3.42 2.91–4.12 3.34 2.75–4.21
Part-time: 0 6.74 2.33–73.68 9.51 2.98–103.76 3.93 1.36–421.60
Part-time: 1-3 3.13 2.35–4.60 3.35 2.33–5.61 3.25 1.99–7.51
Part-time: 4-6 3.04 2.13–5.14 2.45 1.67–4.81 1.91 1.41–3.41
Part-time: 7-9 2.61 1.93–4.05 2.00 1.57–2.92 2.17 1.56–3.84
Part-time: 10+ 2.44 1.82–3.76 1.64 1.33–2.35 3.41 2.17–6.96
Part-time: Overall 3.81 3.29–4.50 4.06 3.39–4.99 3.85 3.03–5.14

Figure S5

Risk associated with in-person schooling by number of reported mitigation measures for alternative COVID-19-related outcomes. Odds ratio of alternative COVID-19-related outcomes by full- and part-time in-person schooling and number of school-based mitigation measures compared to no in-person schooling, adjusted for individual- and county-level covariates. “Overall” indicates adjusted odds ratios of full-time and part-time schooling with any number of mitigation measures compared to no in-person schooling across the Spring Semester 2021 (Jan 12. – Jun 12.). Alternative COVID-19-related outcomes include COVID-like illness in any household member (blue), a household member testing positive for SARS-CoV-2 (green), and the survey respondent testing positive when the test was indicated (purple) and when it was not indicated (orange). High uncertainty around non-indicated positive tests reflects a small sample size (533 total non-indicated positive tests).

Figure 6

Risk associated with in-person schooling and Alpha/Delta variants over time. Estimated baseline risk (top panel) associated with the proportion of cases due to the Alpha and Delta variants and interaction with part-time (middle panel) and full-time (bottom panel) in-person schooling status. Interaction terms show the additional impact of the variant on top of baseline risk due to part- and full-time in-person schooling. Risk is shown within two-month time strata.

Table S6

Relative odds of COVID-19-related outcomes corresponding to a 10% increase in variant prevalence (A) and interaction between variant prevalence and full- and part-time in-person schooling representing the increase in relative odds among comparted to those without children in part-time (B) and full-time (C) schooling, stratified by time period.

Variant term Test+ COVID like illness Loss of taste/smell
adj OR 95% CI adj OR 95% CI adj. OR 95% CI
January to June
Variant Prevalence (A) 1.05 1.03–1.06 1.05 1.03–1.06 1.02 1.01–1.03
Full-time*Variant Ineraction (B) 0.99 0.97–1.00 0.96 0.95–0.98 0.99 0.97–1.00
Part-time*Variant Ineraction (C) 1.04 1.02–1.05 1.05 1.03–1.06 1.05 1.03–1.06
January to February
Variant Prevalence (A) 1.03 0.97–1.10 1.00 0.91–1.10 0.92 0.86–0.98
Full-time*Variant Ineraction (B) 1.04 0.96–1.12 1.05 0.94–1.18 1.04 0.97–1.12
Part-time*Variant Ineraction (C) 1.01 0.92–1.10 1.06 0.95–1.19 1.12 1.04–1.22
March to April
Variant Prevalence (A) 1.13 1.10–1.17 1.11 1.08–1.15 1.09 1.06–1.12
Full-time*Variant Ineraction (B) 0.94 0.91–0.98 0.93 0.90–0.97 0.95 0.92–0.98
Part-time*Variant Ineraction (C) 1.00 0.97–1.05 1.01 0.97–1.05 1.01 0.98–1.04
May to June
Variant Prevalence (A) 1.13 0.99–1.30 1.24 1.11–1.38 1.18 1.08–1.28
Full-time*Variant Ineraction (B) 0.89 0.76–1.03 0.83 0.74–0.92 0.88 0.80–0.97
Part-time*Variant Ineraction (C) 1.01 0.86–1.19 1.02 0.91–1.13 0.95 0.86–1.04

Figure S6

Risk associated with in-person schooling and Alpha/Delta variants over time adjusted for cumulative incidence. Estimated baseline risk (top panel) associated with the proportion of cases due to the Alpha and Delta variants and interaction with part-time (middle panel) and full-time (bottom panel) in-person schooling status. Interaction terms show the additional impact of the variant on top of baseline risk due to part- and full-time in-person schooling. Risk is shown within two-month time strata. Results are adjusted for all baseline covariates as well as cumulative incidence.

Figure 7

Correlations between vaccination, in-person schooling, and mitigation measures. Pearson’s correlation coefficients between percent vaccinated with at least one dose of a COVID-19 vaccine, percent of respondents living with school-aged children reporting in-person schooling, and average number of school-based mitigation measures by county-month. Results are shown within time periods Jan. 12 to Feb. 28 (left), Mar. 1 to Apr. 30 (center), and May 1 to Jun. 12 (right). All coefficients shown were significant (p < 0.05). Limited to county-months with at least 5 respondents.

Figure 8

Risk associated with in-person schooling and number of vaccine doses. (A) Odds ratio of COVID-19-related outcomes by number of reported vaccine doses (0, 1 or 2) and in-person schooling status (living in a household with a child participating in any in-person (Any IP) or no in-person (No IP) schooling), adjusted for individual- and county-level covariates. Zero vaccine doses and any in-person schooling is the reference group. (B) Odds ratio of COVID-19-related outcomes with one and two vaccine doses compared to zero doses, when data are stratified by none, part-time, and full-time in-person schooling. (C) Odds ratio of COVID-19-related outcomes with part- and full-time in-person schooling compared to no in-person schooling when data are stratified by vaccine doses.

Table S7.

Relative odds of COVID-19-related outcomes A) by number of reported vaccine doses and living in a household with a child participating in any or no in-person schooling compared to zero vaccine doses and any in-person schooling, B) with one and two vaccine doses compared to zero doses when data are stratified by none, part-time, and full-time in-person schooling, and C) by part- and full-time in-person schooling compared to no in-person schooling when data are stratified by vaccine doses.

Category Loss of taste/smell COVID like illness Test+
adj. OR 95% CI adj OR 95% CI adj OR 95% CI
A) OR by vaccine doses and in-person schooling
0 dose & No in-person 2.49 2.40–2.59 2.38 2.26–2.51 2.38 2.29–2.47
1 dose & Any in-person 1.51 1.46–1.57 1.67 1.57–1.78 1.54 1.48–1.60
1 dose & No in-person 1.39 1.35–1.45 1.48 1.40–1.58 1.42 1.36–1.48
2 dose & Any in-person 1.55 1.51–1.60 1.91 1.82–2.01 1.43 1.38–1.48
2 dose & No in-person 1.29 1.25–1.33 1.51 1.43–1.61 1.17 1.14–1.20
B) OR by vaccine doses, stratified by in-person schooling
Full-time: 1 dose 1.53 1.47–1.60 1.72 1.61–1.86 1.59 1.51–1.68
Full-time: 2 dose 1.58 1.53–1.64 1.99 1.87–2.12 1.51 1.44–1.60
None: 1 dose 1.45 1.40–1.52 1.55 1.46–1.67 1.50 1.43–1.58
None: 2 dose 1.34 1.30–1.40 1.61 1.50–1.75 1.20 1.16–1.24
Part-time: 1 dose 1.49 1.39–1.62 1.56 1.39–1.83 1.45 1.36–1.58
Part-time: 2 dose 1.31 1.25–1.39 1.51 1.38–1.69 1.17 1.13–1.23
C) OR by in-person schooling, stratified by vaccine doses
0 dose: Full-time 3.36 3.20–3.54 3.86 3.57–4.19 3.81 3.60–4.05
0 dose: Part-time 3.50 3.32–3.69 3.77 3.51–4.06 3.01 2.86–3.18
1 dose: Full-time 3.49 2.98–4.20 4.44 3.44–6.05 4.30 3.51–5.44
1 dose: Part-time 3.39 2.88–4.10 3.29 2.67–4.24 3.17 2.66–3.89
2 dose: Full-time 4.09 3.49–4.91 4.57 3.70–5.85 4.03 3.19–5.35
2 dose: Part-time 4.52 3.82–5.46 4.06 3.40–4.97 5.28 4.01–7.36